R&D study of a calorimeter has been performed for the next generation electron-positron collider experiment. A prototype module was constructed which consisted of lead and scintillating fibers. It had a combined function both for electromagnetic shower and for hadronic shower. In order to obtain a good energy resolution for hadronic shower, the composition of lead and scintillating fibers was arranged to be 4 : 1. Basic performances were tested using the test beam facility of Proton Synchrotron at National Laboratory for High Energy Physics (KEK). The beams used were electron and negative pions of 1 GeV to 4 GeV.Various properties such as energy resolution, position resolution, and dependence on the incident position were measured. The energy resolution of 14% (50%) at 1GeV incident energy was obtained for electrons (pions). The constant term of 12% was included in the hadronic energy resolution, which was mainly due to the shower leakage. The results obtained in the beam test were compared with the predictions of GEANT simulation program, and the good agreement was obtained.Based on information of lateral shower development and on pre-shower output, the separation between electrons and pions was performed. The separation was also tried by using the time information of the shower development.In parallel with the study of the calorimeter itself, the photon detection devices were also investigated which can be operated in the strong magnetic fields.Based on the beam test results, we found that the prototype calorimeter would satisfy the various requirements from the viewpoint of physics analyzes. It should be noted, however, that the method of mass-production and possibility of cost-down have not been investigated here and will be the future issues.